MTA Sip MIBs

hello many expert in our house.
Could help me about OID of SIP point?
in point below i needs to enable Call waiting via snmp MIBs(on *** line). can i do it?
i try many way to open and doesn't work.

Number Active Voice Lines = 2
Feature configuration for line 0:
Warm Line Number = (0 of 32 bytes)

Forwarding Number = (0 of 32 bytes)

Call Waiting = disabled ****************************
Do Not Disturb = disabled
CLID Blocking = disabled
Reject Anonymous = disabled
Network Privacy = disabled
Warm Line = disabled
Call Forward Busy = disabled
Call Forward No Answer = disabled
Call Forward Unconditional = disabled
Feature configuration for line 1:
Warm Line Number = (0 of 32 bytes)

Forwarding Number = (0 of 32 bytes)

Call Waiting = disabled ********************
Do Not Disturb = disabled
CLID Blocking = disabled
Reject Anonymous = disabled
Network Privacy = disabled
Warm Line = disabled
Call Forward Busy = disabled
Call Forward No Answer = disabled
Call Forward Unconditional = disabled
Console/emta/sip> cd ..

Active Command Table: EMTA Command Table (emta)

Console -> emta

thanks and sorry for my language skill.
- -.